The Alexander Maconochie Centre, where an inmate was allegedly assaulted on Sunday morning. Photo: Rohan Thomson.

The Canberra Times understands that King was attacked as he mixed with other prisoners during the distribution of medication. But it is unclear how a child sex offender, usually separated from most of the prison population for their own protection, came to be attacked.

Police say they believe a 27-year-old inmate carried out the assault and they were continuing to investigate. The spokesman said the motive for the alleged assault was yet to be determined, but initial reports indicated it was unprovoked.